Chicago Marathon
Race Day Weather
Mild conditions, strategic pacing needed
Runners will face a mild temperature trend, starting at 57°F and finishing at 59°F. A light headwind in the early miles will transition to beneficial tailwinds later, especially between Miles 3-8 and 24-27. With humidity at 71%, it's advised to start conservatively and hydrate frequently, particularly during the headwind segments from Miles 9-23.
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Race Info
The Chicago Marathon starts and finishes in Grant Park, looping through 29 Chicago neighborhoods and crossing the Chicago River six times. The flat, fast course is a Boston qualifier and has produced seven marathon world records, most recently Ruth Chepng'etich's 2:09:56 women's mark in 2024. It's one of the seven Abbott World Marathon Majors, held every year on the second Sunday of October.
